Comparison of a calcium antagonist and an ACE inhibitor in the treatment of elderly hypertensive patients

Abstract

The antihypertensive efficacy of the calcium antagonist amlodipine and of the ACE inhibitor enalapril were compared in a randomized, parallel group, double-blind, 3-month study. Seventy-two elderly patients (age ≥65 years, of both sexes) with mild-to-moderate hypertension (DBP ≥95 ≤110 mmHg, SBP ≥160 ≤200 mmHg) were included in the study. After a 2-week run-in washout period, patients were randomized to receive amlodipine 5 mg/day (36 patients, 19 men and 17 women, age 70 ± 4 years) or enalapril 10 mg/day (36 patients, 20 men and 16 women, age 72 ± 5 years) for 3 months, followed by a 2-week posttreatment washout period. In both groups, after 1 month of active treatment, the drugs' dosage could be doubled in nonresponders. After 2 months the lower doses of the drugs could be combined in persistent nonresponders. (Patients were considered nonresponders if DBP was >90 mmHg or if DBP reduction was <10 mmHg versus baseline.) Blood pressure and heart rate were recorded every 2 weeks and electrocardiographic and laboratory parameters were recorded every month. Overall, blood pressure was reduced from 175 ± 18/103 ± 8 mmHg to 146 ± 11/83 ± 5 mmHg in the amlodipine group and from 171 ± 19/100 ± 9 mmHg to 147 ± 10/85 ± 7 mmHg in the enalapril group. Twelve patients in the amlodipine group and 9 patients in the enalapril group required the higher doses; 1 patient in the amlodipine group and 7 in the enalapril group received the combination. Blood pressure was already statistically reduced in both groups after 1 month of either amlodipine or enalapril monotherapy, and a clinically relevant rise in blood pressure was found during the 2-week posttreatment washout period, in both groups. There were very few mild side effects and no significant changes in laboratory parameters. Tolerability was judged good or very good by all the patients. Amlodipine and enalapril and their combination have proven effective and safe in elderly hypertensive patients.